What it is
The bluebuck, or blue antelope (Hippotragus leucophaeus), was a relative of the roan and sable, confined to the southwestern Cape. IUCN lists it as Extinct. A bluish sheen on the coat gave the name; few mounted skins survive.
Range
A small strip of the Cape Floristic Region, South Africa. Even at European contact the range was already limited.
What happened
Dutch and later settlers hunted it and converted grazing to livestock. The last animals were taken around 1799-1800. It is generally called the first large African mammal driven to extinction by colonial hunting. Pre-colonial hunting and a naturally small range likely made the end faster; the documented last step is settler overkill.
When / status
Extinct around 1800.
Human role
Colonial hunting and pasture conversion of a species already restricted to a small Cape range.
Sources
IUCN Red List (Hippotragus leucophaeus, EX); Lichtenstein and later historical compilations; South African mammal Red List assessments.